Table 2

Studies included for preventive measures

Author and yearStudy designCountryExposure/ prevention measureOutcome/
evaluation tool
Main findingsQuality assessment
Cao et al, 20209Qualitative interviewsChinaHCW (n=37)/
Coping strategies as video chats or telephone calls with family and friends
InterviewPsychological support may help buffer negative impact on stress.CASP
(No: n=7, Yes: n=2)
Chen et al, 202039Qualitative interviewsChinaHCW (n=13), stress, influence on mental health/ psychological intervention medical team, hotlineInterviewNot scared to get infected, help for resting, skills to cope with patients’ anxiety and PPE shortage neededCASP
(No: n=5, Yes: n=2, can’t tell: n=2)
Chen et al, 202034Ecological studyChinaCaesarean delivery (n=17)/ appropriate PPE (N95 masks, goggles, protective suits, disposable caps, rubber gloves), if endotracheal intubation air-purifying respirator ; negative operating room,RT-PCRNo medical staff involved in operation were infectedGRADE: very low
Htun et al, 202036Cross-sectional studySingaporeHospital overall (staff n=10 583)/
Fever and sickness surveillance for staff; risk-based PPE; enhanced surveillance for unwell staff
Mixed (clinical assessment, swabs for PCR)No infection with COVID-19AXIS: positive aspect n=10, negative n=4, don’t know n=6
Huang et al, 202035Ecological studyChinaNurses, 35 confirmed, 260 suspected cases/
PPE (hat, respirator, inner gloves, eye mask, protective clothing. Shoe covers, isolation gowns, outer gloves, face shield), hand hygiene, ward disinfection, medical waste management, sterilisation of patient care devices, management of occupational exposure. Teaching. Shift schedule evaluated; psychological counselling
Not specifiedZero infection rate in nursesGRADE: very low
Huang et al, 202030Ecological studyChinaRadiology department, 3083 suspected or confirmed COVID-19 patients/ Reconfiguring of the department, PPE (protective clothing, surgical cap, N95 mask, gloves, face shields, goggles), training, donning and doffing under supervision, strategic planning of examination proceduresClinical symptomsNone of the staff became infected.GRADE: very low
Kabesch et al, 202038Ecological studyGermanyOutbreak scenario, midwife → colleagues /
Face masks, social distancing in cafeteria and break rooms, on site visits hygiene experts, staff training, transparent, timely and direct communication, testing all symptomatic employees
Laboratory test for symptomatic staffSuccessful containment of the outbreak within 3 weeks, 36 staff members tested positiveGRADE: very low
Malik 202033Ecological studyPakistanAdmission of a COVID-19 positive patient to the ICU/
HCW with N95 or surgical masks
PCRAll HCW (n=34) tested negative for COVID-19GRADE: low
Ng et al, 202032Ecological studySingaporeone patient with pneumonia/
HCW (n=41) exposed during aerosol-generating procedures
Clinical monitoring and PCRNo HCW infectedGRADE: low
Wee et al, 202031Ecological studySingaporeEmergency department, PCR tests for all patients with respiratory syndromes, n=70 patients tested positive/
PPE risk stratified
PCR testing, extensive surveillanceNo nosocomial transmissionGRADE: low
Zhu et al et al, 202037Ecological studyChinaone patient with endonasal adenoma resection, general care and operation/ no prevention measures initially before confirmed infectionDiagnosis of infection not specified.four nurses without prevention measures (and 10 persons without contact to the patient) got infected, none of the persons in the operation room or under specific prevention got infected.GRADE: very low
  • AXIS, Appraisal Tool for Cross-Sectional Studies; CASP, Critical Appraisal Skills Programme; GRADE, Grading of Recommendations, Assessment, Development and Evaluations; HCW, healthcare worker.